Heretofore, as semi-conductive belts usable as intermediate transfer belts for electrophotographic recording devices, there has been known semi-conductive belts using films formed of vinylidene fluoride, ethylene-tetrafluoroethylene copolymers, polycarbonates, and the like. Moreover, in order to solve problems of crack generation at edge parts of the belts owing to insufficient mechanical properties such as strength, friction resistance and wear resistance, deformation of transferred images owing to deformation by load at driving, and the like, there has been known a belt wherein volume resistivity is controlled to 1 to 1013 Ω·cm by mixing a conductive substance into a polyimide film.
The semi-conductive belts as above are generally produced by a method wherein a starting solution containing a resin, a conductive substance, a solvent, and the like is seamlessly applied to inside of a cylindrical mold and then is dried and cured to form a film.
However, in the production method as described above, at the time when the belt is peeled from the mold, there is a case that a geometrically defective part such as a small protrusion and/or fold may formed on the belt surface. With recent developments in high-quality and high-speed electrophotographic recording devices, a belt having such a defective part causes troubles in images and thus cannot be used as an intermediate transfer belt or a transfer-convey belt, so that a product yield becomes worse at the production of a semi-conductive belt.
Thus, the present applicant has invented a method for correcting a semi-conductive belt capable of enhancing a product yield by subjecting the belt to heat treatment to flatten it even when a geometrically defective part is generated at the production step or the like (see, Reference 1).
[Reference 1] JP-A-2002-365926
However, the method for correcting a semi-conductive belt wherein a geometrically defective part is flattened by heat treatment alone cannot completely flatten all geometrically defective parts and thus there exists room for improving a product yield.